Gas seals or dry gas seals of the type defined in the introduction are already known from various publications. Examples of these are WO2014/037150 and WO2014/023581.
Dry gas seals of said type generally comprise components composed of ceramic, in particular manufactured from silicon carbide or tungsten carbide. The ceramic components are normally the stationary and/or rotating slide rings and, if appropriate, adjoining elements. A further example from the patent literature is given by DE 39 25 403 C2.
A gas seal of the type defined in the introduction is already known from EP 0 177 161 A1. EP 0 315 941 A2 presents the use of a spiral spring for the concentric connection of two components composed of different materials.
The thermal expansion of these ceramic materials amounts to approximately 3.5×10−6 m/K times meters. In comparison with this, the thermal expansion of steel, that material which is generally fitted adjacent to these ceramics of the seals, amounts to approximately 11×10−6 m/K times meters. The relative expansion between the ceramic components and the steel components resulting from this difference between the coefficients of thermal expansion has to be compensated accordingly, and so simple fastening of the ceramic shaft seal components to the steel components is not an option.